At the age of 78, in a moment of whimsey, Benjamin Franklin wrote An Economical Project, a discourse on the thrift of natural versus artificial lighting. He included several funny regulations that Paris might adopt to help. Over two centuries later, nations around the world use a variation of his concept to conserve energy and more fully enjoy the benefits of daylight.

Benjamin in Paris

As he neared the end of his long tenure as American delegate in Paris, Benjamin Franklin felt his years. Gout and gallstones hampered his movements and left him virtually confined to his house in the Parisian suburb of Passy. Such restrictions to a man of Franklin's dynamic and social nature would have been vexing indeed had he not the company of close friends, men like Antoine Alexis-Francois Cadet de Vaux, editor of the Journal de Paris, who encouraged him to work on simple, yet important, problems. To show his appreciation to these comrades, Franklin penned a series of bagatelles for their amusement.

One such piece took the form of a letter to the Journal de Paris concerning the economy of lighting in the home, which Franklin wrote after attending the demonstration of a new oil lamp. In it, he parodied himself, his love of thrift, his scientific papers and his passion for playing chess until the wee hours of the morning then sleeping until midday. His friend Cadet de Vaux published the letter in the Journal on April 26, 1784, under the English title An Economical Project. Franklin began the letter by noting that much discussion had followed the demonstration of an oil lamp the previous evening concerning the amount of oil used in relation to the quantity of light produced. This he followed with details of how a great discovery of an avenue of thrift came to him.

The Parisians never woke before noon

Franklin had eventually bedded down at three or four hours past midnight but was awakened at six in the morning by a sudden noise. Surprised to find his room filled with light, Franklin at first imagined that a number of the new oil lamps were the source, but he soon perceived the light to be originating from the outside. Looking out the window, Franklin saw the sun rising above the horizon, its rays pouring through the open shutters.

"I looked at my watch, which goes very well, and found that it was but six o clock; and still thinking it something extraordinary that the sun should rise so early, I looked into the almanac, where I found it to be the hour given for his rising on that day. I looked forward too, and found he was to rise still earlier every day towards the end of June; and that no time during the year he retarded his rising so long as till eight o clock. Your readers, who with me have never seen any sign of sunshine before noon, and seldom regard the astronomical part of the almanac, will be as much astonished as I was, when they hear of his rising so early; and especially when I assure them, that he gives light as soon as he rises. I am convinced of this.

Sly Franklin claimed that a noted philosopher assured him that he was most certainly mistaken, for it was well known that "there could be no light abroad at that hour." His windows had not let the light in, but being open, had let the darkness out.

"This event has given rise in my mind to several serious and important reflections," the letter continued. Had he not been aroused at so early a morning hour, he would have slept until noon through six hours of daylight and therefore, living six hours the following night by candlelight. Realizing the latter was much more expensive than the former, he began calculating, for the sheer love of economy, the utility of his discovery -- the true test of any invention.

On the assumption that 100,000 Parisian families burned half a pound of candles per hour for an average of seven hours per day (the average time for the summer months between dusk and the supposed bedtime of Parisians), the account would stand thus:

"183 nights between 20 March and 20 September times 7 hours per night of candle usage equals 1,281 hours for a half year of candle usage. Multiplying by 100,000 families gives 128,100,000 hours by candlelight. Each candle requires half a pound of tallow and wax, thus a total of 64,050,000 pounds. At a price of thirty sols per pounds of tallow and wax (two hundred sols make one livre tournois), the total sum comes to 96,075,000 livre tournois.

"An immense sum," the astonished Franklin concluded, "that the city of Paris might save every year."

Some "new" regulations

To answer skeptics who cried that old habits are hard to change, and it would be difficult to induce the population of Paris to rise before noon, Franklin proposed the following regulations:

A tax be laid on every window built with shutters to keep out the light of the sun.

Candles rationed to one pound per family per week, and the regulation enforced by the constabulary.

Guards posted to stop the passage of all coaches, etc. upon the streets after sunset except those of physicians, surgeons and midwives.

Every morning as soon as the sun shall rise, church bells and, if necessary, cannon shall inform the citizenry of the advent of light and "awaken the sluggards effectually and make them open their eyes to see their true interests ... All the difficulty will be in the first two or three days; after which the reformation will be as natural and easy as the present irregularity. ... Oblige a man to rise at four in the morning, and it is probable he will go willingly to bed at eight in the evening."

Future of the idea

The great discovery, conceived in humor and reported with all the wit and wisdom of Poor Richard was not soon forgotten. Cadet de Vaux reprinted the article on November 30, 1785. Messrs Quinquet and Lange, inventors of the oil lamp that sparked the idea, were so taken by the scheme that they continued corresponding with Franklin even after he returned to America.

Franklin continued to think about the scheme, and it may have prompted this description of 18th-century London written in his autobiography:

"For in walking thro' the Strand and Fleet Street one morning at seven o clock, I observed there was not one shop open tho it had been daylight and the sun up above three hours -- the inhabitants of London choosing voluntarily to live much by candlelight and sleep by sunshine, and yet often complaining a little absurdly of the duty on candles and the high price of tallow."

Decades later, church bells and cannon to rouse a sleeping populace were replaced by the simple act of altering the hands on clocks in the spring as the hour of dawning becomes too early for most sleepy eyes. In 1973, for the second time in American history, the Congress declared the year-round use of Daylight Saving Time to save energy during the oil embargo as a general concern for the nation's good and a love for economy. Today as fossil fuel supplies diminish and increase in price and their use damages the environment, we need to heed Franklin's advice still again.